1. Field of the Invention
The present invention relates to an electronic control unit and a vehicle behavior control device using the electronic control unit.
2. Description of the Related Art
A vehicle behavior control device for stabilizing the behavior of a vehicle like a car includes electric parts, such as an electromagnetic valve and a pressure sensor, a motorized part like a motor, a reciprocating pump driven by the motor, a reservoir-configuring part functioning as a reservoir, a control board for controlling operations of the electromagnetic valve and the motor, and a base body which has brake fluid paths formed therein and is assembled with the foregoing various parts.
In the foregoing vehicle behavior control device, a sensor which detects the behavior of a vehicle body is incorporated in the control board. The control board controls the operations of the electromagnetic valve and the motor based on the behavior of the vehicle body detected by the sensor to change the brake fluid pressure in the brake fluid paths, thereby controlling the braking force of a brake. Accordingly, the behavior of the vehicle is then stabilized.
As an example, an electronic control unit for the foregoing vehicle behavior control device has a sensor board equipped with a sensor, a control board which controls the operations of an electromagnetic valve and a motor based on the behavior of a vehicle body detected by the sensor, and a housing which accommodates the sensor board and the control board in a stacked condition. According to the conventional electronic control unit, the housing has a recess protruding toward the exterior formed at the internal face of the housing, and the sensor and the sensor board are accommodated in the recess (see, for example, JP2005-200013A, paragraph 0015, FIGS. 2 and 3).
According to such an electronic control unit, since it is unnecessary to connect the sensor with the control board using a part like a harness, the number of parts can be reduced. Moreover, since it is unnecessary to accommodate the sensor and the electronic control unit separately inside the vehicle, the size and weight of the vehicle can be reduced.
Furthermore, since it is unnecessary to attach the sensor to the control board, it is unnecessary to use a large area for the control board.
Still further, since a target when the sensor is inspected and adjusted is merely the sensor board, efficiency in the sensor inspection/adjustment procedure can be improved.
Yet further, when the specification of the sensor is changed, it is necessary to change parts of the sensor board only, and it is unnecessary to change parts of the control board, so that it is possible to reduce the cost and the work hour inherent to the change of the specification of the sensor.
According to the foregoing conventional electronic control unit, however, since a portion where the sensor is accommodated protrudes from the external face of the housing, there is a problem that the size of the housing becomes large.
It is, therefore, an object of the present invention to provide an electronic control unit and a vehicle behavior control device using the electronic control unit, which can miniaturize a housing in which a sensor board and a control board are accommodated, thereby making the whole electronic control unit compact.